Understanding Aperture

There are three key components of the “exposure triangle”, Aperture, ISO and Shutter Speed, and today we will be talking about Aperture.

An easy way to think of the Aperture of your lens is to think in terms of the human eye. Since your camera’s sensor “sees” things much as your eye does and then records those images in a physical form, we can think of Aperture the same way.

Every lens is made of a a group of glass elements and also a group of Aperture blades. The blades are what limits the amount of light passing into the lens and onto your sensor. These mechanical blades work the same way your pupil works, when in a low light situation, your pupils open up larger to allow more light in so that you can see better and when you are out in bright sunlight, they shrink down to tiny dots to reduce the amount of light coming in.

My Canon EF 50mm F/1.4 USM wide open at F/1.4

Aperture blades do the exact same thing, only mechanically and you control them. So a wide Aperture lens like my Canon EF 50mm F/1.4 USM when set at 1.4 is wide open, like your pupil is in low light and I can shoot better indoors at say a concert.

When I am shooting outdoors in sunlight, I will generally set my Aperture to say F/5.6 to F/8 and the blade will reduce the size of the hole in the center of my lens allowing less light into my sensor like the image below of the Canon EF 50mm F/1.8 II. The process of engaging the blades in your lens is known as stopping down as you are reducing the amount of light getting through the lens to your sensor.

Stock image of Canon EF 50mm F/1.8 II with the blades closed all the way

 Aperture is measured in stops and you will see it marked on your lens in the following values. Let’s say you have a standard kit lens of 18-55mm. That lens generally has an Aperture of F/3.5-F/5.6, which means at 18mm it can open as wide as F/3.5 but at 55mm it can only open to a width of F/5.6.

If you are looking at the popular 70-200mm lenses, they generally come in two varieties, F/2.8 and F/4. The F/2.8 model will allow more light, in this case one stop more, than it’s F/4 counterpart.

Aperture also directly impacts your Depth of Field in your images, especially in longer focal length lenses. We all strive to achieve that creamy background blur and bokeh, and using a low Aperture with a longer focal length lens is how that is accomplished. This is one of the reasons wedding photographers will generally shoot with the 135mm F/2 or the 70-200mm F/2.8 lenses. How your bokeh looks in your images depends on how many blades your lens has. A five blade lens will not be able to make perfect circles, but then again, some people like their bokeh to be more angular, where I prefer mine to be as close to perfectly rounds balls of light. When shooting landscapes, by stepping down the Aperture, you can keep more of the scene in focus and get that beautiful wide shot where everything looks fantastic!

Notice the creamy Bokeh in this shot I took in Monroe, Ga.

 Another thing to keep in mind is that every lens has a “Sweet Spot”, which means the Aperture at which the lens shoots at it’s sharpest. You will need to test your lenses for yourself to find that “Sweet Spot” area, but on most lenses, it’s the area between F/5.6 and F/9.

Janice Mcgregor shot this one with the Canon EF 28-135mm check out that blurry background!

 Understanding Aperture is crucial to become a successful photographer and once you master this aspect of your lenses you will becomes more skilled and intuitive at fine tuning your photography.



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Wide-Angle Wednesday

Good Morning PSPN and Welcome to Wide-Angle Wednesday!

My name is Corina and I’m a student studying in the BS Photography program. I just recently celebrated my first year at AI and look forward to blogging all about my experience and everything photography right here every Wednesday.

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Why call it “Wide-Angle” Wednesday? Because “Hump Day” is over rated...dang camel!

Let’s see, a wide angle lens serves a purpose in two ways

• ·        Gives you a wide angle of view
• ·     Shorter focal length

The goal in blogging here at PSPN is to provide that wide-angle view in both our course study and our love for photography. It’s an opportunity to add emphasis and detail to your foreground studies, as you capture and hone your skills in the background. A shorter focal length is not a bad thing; it represents your passion to be up close and personal to your studies.

Take advantage of Wide Angle Perspective!

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We have a wide angle view meaning objects up close will seem bigger in size than that of the background. Naturally in life, our short term goals are in the foreground and the long term goals fall into the background. We all strive to meet our long term goals but we can’t achieve perspective without the short term being upfront and completed first.  

So where am I going with the photography, wide angle lens lingo on a Wednesday?

Well I like to make comparisons and normally when I do, I use something recognizable to the audience. I’m also an inspiring landscape photographer, with a side of journalism. As photographers we may take a second or two to determine what lens we need, lighting, accessories, and settings we plan to use to capture the image. Sometimes the outcome is awesome, other times the outcome is a shot being missed. Let your time here be that awesome shot, in other words take more than a second to determine what you need as you go forward in learning new skills.   

We have all heard the saying “cross your t’s and dot your i’s”. I like to take it one step further and say don’t forget to capitalize your Education Opportunities and don’t let the assignment be the period to the end of practicing your new skills.

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My photography inspiration comes from growing up in the Yosemite Valley in California. Anyone from the area has probably seen the works of Ansel Adams a thousand times over. At some point I thought an awesome job in life would be a Forest Ranger. Little did I know I would fall in love with the art, and the history behind the images. I still have a passion for the environment and being outdoors, I just rather wear a camera than a uniform. Below is a quote also well-known and used a lot in the photography world.

"You don’t make a photograph just with a camera. You bring to the act of photography all the pictures you have seen, the books you have read, the music you have heard, the people you have loved.” –Ansel Adams

In closing, let your path in photography be wide angled. Stay focused and your path will be filled with perfect shots. 

I look forward to next week's Wide-Angle Wednesday as it’s Christmas! Good day to capture memories and eat some good food.

From my camera to yours, may all your images tell a story!

The Wednesday Ambassador